Vertically-adjustable seat



(No Model.)

J. R. BURKE. VERTIGALLY ADJUSTABLE SEAT.

Patented Oct. Z0, 1896.

UNITED STATES PATENT EErcE.

JOHN RYAN BURKE, OF BOSTON, MASSACHUSETTS.

VERTlCALLY-ADJUSTAB LE SEAT.

SPECIFICATION forming part of Letters Patent N O. 569,809, dated October 20, 1896.

Application filed July 25,1895.

To all whom t may concern/s Be it known that I, JOHN RYAN BURKE, of Boston, county of Suffolk, State of Massachusetts, have invented an Improvement in `Vertically-Adjustable Seats, of which the following description, in connection with the accompanying drawings, is a specication, like letters on the drawings representing like parts.

This invention has for its object the production of a novel vertically-adjustable and preferably non-rotatable seat, the invention being particularly adapted for use in connection with piano stools or seats.

In the drawings, Figure l, in side eleva tion, partial section, shows a seat embodying my invention; Fig. 2, an enlarged section of the upper portion of Fig. l; Fig. 3, a View of a portion of the parts, Fig. 2, butin different position; and Fig. il, a horizontal section on the dotted line a1, Fig. 2. Figs. 5 and (5 are detail views of the slotted head provided to prevent rotation of the seat relatively to its support. l

Referring to the drawings, in the particular embodiment of my inven tion there shown and selected for illustration the support A is preferably tubular to contain all the moving parts, and is provided, it may be, with one or more supporting-legs e c at its bottom.

The tubular portion of the support A is shown as provided with a cap or end a', (shown as more or less ornamentah) and which may be screwed into the end of the tubular portion, as shown, the said cap in the present instance being threaded interiorly to receive the post l), (shown as rectangular in crosssection,) and provided with oppositclyarranged laterally-extended teeth or projections b providing engaging surfaces to be hereinafter referred to.

The seatframe C is herein shown as provided at its under side with a suitable casting c, in which is screwed the tubular seatcarrying member c', to the lower end of which I have applied a suitable head o2, provided at its lower end with a piston-disk c3, to be referred to.

The head c2, as herein shown, has pivoted to it at opposite sides, at c4, two locking or engaging devices c5, which at their lower ends are adapted to engage and lock with the engaging surfaces of the projections ZJ upon the post l), which stands within the tubular carrying member c', the engaging ends of the said devices c5 being preferably forked, as shown, to coperate with two of the en gaging surfaces at each side of the post l).

To engage and release the devices c5 with the engaging surfaces on the post l), l have provided withinl the carrying member c' an operating member d, also preferably tubular, and at its lower end adapted to engage the beveled faces c of the devices c5, so that when the said operating member is depressed it will act upon the said beveled surfaces and spread the lower engaging ends of the devices c to release them from the engaging surfaces of the post b to enable the seat to be raised and lowered. This movement of the operating member may be ellected in suitable manner, herein by means of an operating-l1andle d", shown as pivoted at d2 to the seat-frame and jointed at one end to the top of the operating member and acted upon at its outer end by a suitable spring di, tending to depress the handle-lever and raise the operating member. p

lVhen raised, the operating member d, at its lower end, stands between the inturned ends ci of the pivoted locking devices ci' and holds the latter spread with their lower engaging ends locked with the projections on the post I).

Then the operating member is depressed to spread the locking devices, these inturned ends cT enter openings (Z4 in the operatin g member, and when the said operating member is again raised the lower walls of these openings engage the beveled under sides of the inturned ends c7 of the locking devices c5 and turn the latter into engagement with the projections on the post b.

In the preferred embodiment of my invention the head c2 and operating member d are slotted at their opposite sides, as at dx, to receive the post l), to therebyv prevent rotation of the seat upon its support, the construction preferably providing for a vertical adjustment or movement only.

To avoid any shock due to suddendropping of the seat upon its support, I have thickened the walls of the tubular portion of the support A at or near the bottoni of the IOO said support, as at ax, (see Fig. 1,) to a diameter slightly in excess of that of the piston-like head c3, referred to.

In the normal adjustment of the seat above the thickened portion ax the piston-head c3 moves freely within the tubular portion of the support without having any retarding effeet, but should the seat suddenly drop, by reason of careless manipulation during adjustment, when the piston-head c3 enters the reduced portion of the support at ax, the escape of air from beneath the said head c3 is restricted, so that the lower portion of the support acts in the nature of a dash-pot to cushion the downward movement and avoid an objectionable shock, the latter part of the downward movement being necessarily slow.

The carrying mem ber c' is preferably guided at the upper end of the support in suitable manner, as by the cap a2.

My invention is not limited to the particular embodiment herein shown, for it is evident the same may be varied without departing from the spirit and scope of the invention.

I claim- 1. A supporting member, a seat, and a seatcarrying member, a series of engaging surfaces on one and one or more locking devices on the other of said members constructed to interlock with the engaging surfaces and hold the members from movement in either direction, and a vertically-sliding operating member arranged to reciprocate between said members for operating the said locking device, substantially as described.

2. A supporting member, a seat and a tubular carrying member therefor, a series of engaging surfaces on one and one or more cooperating locking devices on the other of said members, constructed to interlock with the engaging surfaces and hold the members from movement in either direction and a verticallysliding tubular operating member contained within the said tubular carrying member, and to control the engagement and disengagement of said locking devices, substantially as described.

3. A supporting member having a post provided with a series of lateral engaging surfaces, a seat, and a tubular carrying member therefor, one or more locking devices mount ed at the lower end of said carrying member for and to engage said series of engagingsurfaces, and provided with beveled operatingsurfaces, and a vertically-sliding operating member within said carrying member and adapted to engage said beveled surfaces to positively move said locking devices out ot' engagement With said series of engaging surfaces, substantially as described.

4t. The supporting member, the post provided with lateral engaging surfaces, the seat, and carrying member therefor provided with the pivoted locking devices having beveled operating-surfaces at their lower ends and inturned portions at their upper ends, the vertically-sliding operating member within the said carrying member arranged to engage said beveled operating-surfaces, and provided with the openings d4, to receive said inturned portions, operatingsubstantially as described.

5. A supporting member, a post having lateral engaging surfaces, a seat, and seatcarrying member, the latter adapted to reA ceive said post and being provided at its lower end with a head, locking devices pivoted in said head to cooperate with said surfaces, and an operating member within said carrying member, said head being provided with a slot below the path of movement of said operating member to receive the said post, to thereby prevent rotative movement without interfering with vertical movement. substantially as described.

6. A supporting member, havinga tubular portion, said tubular portion being less in diameter in its lower end than in the remainder of its length, a seat, and seat-carrying member arranged within said tubular portion of the supporting member, a post provided with engaging teeth and centrally arranged within said tubular portion, one or more locking devices carried on the lower end of said seat-carrying member to engage said teeth, an annular disk xed on said seatcarrying member to fit the lower end of said tubular member and to cooperate with the said lower end of the same to constitute a dash-pot to cushion downward movement of the seat-supporting member within said tu bular member, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JOHN RYAN BURKE. lVitnesses:

FREDERICK L. EMERY, AUGUSTA E. DEAN.

IOO 

